Hydrometallurgical apparatus for the recovery of copper.



y v E. n.4wEmLElN; HYDROMUETALLURGICAL APPARATUS FOR THE RECOVERY UFCOFPEH.

' APPLlcmo mio rn.21. 191e. n I 1,223,454". l Plteuted Apr. 24,1917,

iTLl

f Rom LEncH HNDSTORHGETANKS -fn UNITED STATES PATENTN onirica.`

EDWARD BAY'W'EIDLEINQOF THOMPSON, NEVADA, ASSI( 'rN 0B TO METALS RESEARCH COMPANY, OF NEW YORK, N. Y., A CORPORATION F MAINE.

s. l n HYDBOMETALLUIQQ'IQAL APPARATUS FOB THE RECOVERY 0F COPPER.

Specification of Letters Patent.

Patented Apr. 24, 1917.

Application led February 21, 1916. Serial! i. 79,597.

a Wet way, from its ores.

In my prior Patent No. 1,089,096, granted March 3, 1914, Illiave described and claimed the extraction of copper from copper bearing material by means of sulfuric acid and the precipitation of the copper from theresulting copperfsulfate solution 'b v treatment i with Asulfur dioxid at a suitable temperature and pressure., This precipitation of copper 'is' based generally upon the reversible reac- In therpreferrcd practice of the invention, asdescribed in said prior. patent, 4the 'tem )erature'of about-15()O C. and a pressure .ofi-a ,iout 100 pounds per square inch. -Urider l,these conditions the copper is precipi-.i tated substantially ,quantitativel)T and a leach solution `is produced suitable for releaching purposes.

, lIn lsaid prior patent it uas proposed to leach u'ith the solution as it comes hot from the precipitation tanks. thereby utilizing its niaxinium leaching, etiicieiicy, and. making the princess contini'ious in the sense that the leaching solution is utilized over and over againfffor re-lcacliiug the ore. after the copper has been precipitated each time out of the solution.

Ip. ,my application Serial No. 48,150,4filed Aug: st 3l. 1915, I have described a continuousj'irocess of precipita-ting "copper from copper sulfate solutions by means of sulfur 55 dioxld. which is cmitii-iuousin the sense that 4ore is le'ached With a 3.69? sulfuric acid solu- Y `ai up le100`lbs. per square'inch. T yleading from ihep'ump 6 to the' the solution is continuously passing through the precipitat'ng tank or tanks and is continuously heat ed therein, thereby precipitating the copper and regenerating the sulfuric acid; and I hive further described .the utilization of the Waste heat in the solution `coming .from the precipitating tank4 for.

heating up the, ingoing solution, instead of leaching the ore directly with this hot solu-` tion.

the precipitatirigr reaction is thereby facilitated, while tl' e cooling of the hot leaching solution make:` it Aalso more efficient in that the acid losses are materially reduced by the useof a cooler leachingr and extracting acid.

The present invention relates to apparatus for the practising of such processes, and in particular-for the continuous precipitation of copper acco :ding to the process described and claimed iii my said application-Serial No. 48,150.

The invention uill be described more in detail with ref erencc to the apparatus illustinted, more oi less dlagrammatically, in the 8`0 accompanying draii'ings, hut it. is intended and understool thaty the invention will be illustrated by, out is not limited to, the specific. enibodinitnts thus illustrated and .de-4 scribed.

lu. the accon `panying drawings V Figure 1 slows, partly in section and partly in elevition, the precipitating and heat intcrclianging parts of the apparatus..

Fig. Qshou's in elevation, a modified con-` 90 strurtion similzr to that of Figfl'; and Y F1a. 3 shows in diagr'ani,the arrangement 'of thc apparat is..

Referring first' to Fig. 1, the storage tank for the copper sulfate solution, afterit has beei1 ue'|itrilized and charged withsul- IiurA dioxid (by means not-shown), isindicated at 1, anc. is provided With anA outlet Z haringtherein a regulating valve-3 and` ,leading to. the heat interchangerlof anyiOO.

suitable" `or .praferred constructior'i;V From 4'this heat inter changer the soltitioi'i-passes through the pipe 5 to the pump 6 by means `fot which it is orced into-the precipitating tank 49. undera suitable pressure', 0f, f

tatingftank is provided with an* terl oi jacket 7, and has an upWardly]arranged. discharge end 8 Within thewtankff-lr'lroin 1.1'0

As a result of this heat interchange 65 the copper sulate solution is preheated and egt-v. 105.

vided With a suitable regulating valve 11,l

and is returned thereby to the heat interi -ichanger 4'from which it is in turn forced through the pipes 12 and 14, by means of the pump 13, back to the leach tanks.

The precipitating tank or chamber 9 is suitably supported upon supports 15 and is provided with an outer double Wall or other suitable means for heating by means of oil. Such oil heating I have found to be particularly suitable for maintaining the necessary temperature within the precipitating tank. The oil heater -is indicated at 16, provided withy .a suitable air and gas inle-t 17 and-with a funnel or chimney 18. From y'the heater the oil passes by means of the pipe 19, in part -through the branch 20 to the double wall of the precipitating tank, and in part by the branch 21 to the oil. jacket 7 from which it is then discharged into the double jacketed precipitating tank. The oil is drawn off from the p of the jacket by means of the pipe 22 nd passes down through the pipe 23 to the pump 24 by means of which it is returned to the heater through the pipe 25, the desired circulation of the oil being thus effected. An oil expansion tank is arranged a suitable distance above the top of the circulatory System and is connected thereto by means of pipes 26 and 27.

The precipitating tank s provided with liquid gages 30 for determining the level of the liquid therein, and with openings 31 for the introduction of thermometers. It is also provided at its top with ai safety valve 32 and with a thermometer 33. A suitable pressure gage (not shown) will, in practice, also be provided. Other thermometers 33 are also provided at various points of the apparatus for indicating the tempera-' ture.

The apparatus of Fig. 2 is similar in its construction and operation to that of Fig. 1, and corresponding parts are. indicated .by the same numerals with the sufiix a appended thereto. In this figure, the storage tank is not shown, but the copper sulfate solution, charged with sulfur dioxid, passes through the pipe 2a to the pump 6El by means of which it 'is forced 'through the pipe 5a to the heat'interchangen` This arrangement differs from that of Fig. 1 in that the pump is arranged to force the liquor through the interchanger instead of from the interchanger to .the precipitating tank or tower.

. Where the storage tanks 1 of Fig. 1 are not arranged a siiiiicient distance above the interchanger to give the necessary head of liquor and the necessary pressure therein,

4 the arrangement of the pump ahead of the heat interchanger subjects the interchanger to substantially the same pressure as the precipitating tank and thus prevents loss of sulfur dioxid from ith-e Solution. Acheckvalve 5" is also provide 'l in the pipe 5 leadin from the pump to tlie heat interchanger.

rom the heat -nteruhanger of' Fig. 2 the liquor passes to the precipitating tower where the precipitation takes' place, and the leach liquor returns from the top of the tower to the heat interchanger in the manner indicated above in connection with the arrangement of Fig. 1. The ,valve 11a in the pipe 10 is shown in Fig. 2 as provided with la suitable pressurev regulating device .for automatically regulating the pressure in the precipitating tank and the outflow therefrom. 1

The precipitating tank of Fig. 1 is `provided with a lower compartment 35 communicating with the main tank by :means of a false bottom or vvalve L14, this lower compartment being in turn p rovided with a valve controlled outlet 36. The arrange ment of Fig. 2 is of a similar nature, but an equalizing pipe.40 is provided around the valve 34, this pipe 40 beingir4 turii provided with an equalizing valve, the arrangement being such that the pressure -Within the upper and lower compartmentslcari be equalized before the main valve 34 is'.pe nedl The oil heater 16*t of Fig. 2 has the coils (not shown) for heating the oil ai ranged in a casing above. a masonry or brickwo'rk base forming the combustion chamber of the furnace. The oil circulation and sup ply to the precipitating tank is similnrto that of Fig. 1. the pipe 21a to the oil jacket pipe- 7L and escapes therefrom around the inner pipeJ into thedouble wall of the precipitating tank. The cil expansion tank 28a isplaced a suilicient distance above the top of the precipitating tank so thatV the oil within it will be kept cool.

Oil is circulated through The control of the apparatus is suitably effected, either in an automatic manner or" by suitable regulation, from the control panel 41. This control panel is conneeted,

by a tube 42, with a thermostat arrangedA llti rae

From theheat interchanger the cooled leach ,j solution is returned to a suitable Storage tank. o1' tanks from which it is drawn,.as required, into the leach tanks. The ore or other copper bearing .material is introduced into the leach tanks'a'nd there leaehed with the sulfuric acid leach solution. The ex,- oess acid is then neutraliaed-by the addition ofy calcium carbonate or ordinary liniestone, and the precipitating gypsum is suitably removed by siphoning, ltering or- -the continuous process and circulation above referred to, would tend to precipitate metallic copper Within the leach tanks if the leach solution were' completely neutralized therein, any such precipitated copper renaining lwith the gangue and being thereby ost.- s

The copper sulfate solution from the neutralizing tank should, in the preferred prac-- tice of the invention, contain about 1.5% Sulfur dioxid is next forced into the copper sulfate solution, in suitable amount, and the'solution is then stored in suitable storage tanks, one of which .is indicated in F ig.- 1, from Whichfthe solution is drawn off and passed to the heat inter- `changer 4., Where it is pre-heated by the hot leach liquor. coming Vfrom the top oi the precipitating tower, inthe inanner already described. The pre-heated copper sulfate solution, charged with the sulfur dioxid, is forced I"under a suitable pressureand in a continuous manner into the bottom .of the precipitating tank through the oil jacketedpipe 7 or 7bv in which it is further pre-heated. During the passage up through the piecip1- tating tank, the liquor is heated to thc necessary teinperatuie of about 150O C. for the precipitation ot the copper, the precipitating reaction being substantially complete as soon as the proper conditions ot teinperature and pressure are reached. (e. g., about 100 lbs. pressure and about 150 Q The precipitation of the copper is accoinplislied by the regeneration of twice as inuch `sulfuric acid, theoretically, as required for extracting a corresponding amount of cop` per. The leach liquor containing the regenerating acidis passed through ,the heat inlterclianger where ift serves to pre-heat the ingoing solution and where it is itself cooled to a temperature' below its boilingl point from the niuch higher temperature `ofv the recipitating tank. By thus cooling the yeach liquor before utilizing .it for extracting further, amounts of ore the acid losses in .the hot solution can be n'iateriallyj'rediiced. Thus', in practice, it is possible-to cool-the outgoing solution from about 150? (l for 1600' C. down-` to-aboutQiQ()c C. and at the saine time raise the temperature of the ingoing solution from about'()n to. about The excess acid regeneratedduring the precipitation Which'is not required for the leaching of firther batches of ore is available for use for other purposes, fas will be readily unde: stood. ',There ma i, however, be some loss of acid during the leaching, in dissolving'iron or other constituents, and, there will usi ally be some excess of acid to be neutraliked after the leaching of ore, so that more acd than is theoretically. neces. sary is requii ed for the leaching operation. The precif itating tank or tower is of suitable height to permit the heating therein of the copper sulfate solution to the proper temperature, a. g., about 150' C., although in the upper pait of the apparatus this temperature r-iay be exceeded. Since the reaction is corni `lete as soon as the proper teniperature and pressure are. attained, the cop per will be th -n precipitated and Willfall to the bottoni ot the tank, thus being withdrawn from he 'sniper and hotter part of 55 the tank into the cooler pai-ts below, from which it 'u' i.ii lra.n'ii into the lower coinpartnient in tl ic manner above indicated.

A constant pressure can be maintained within the 'piecipitataing tank by suitable regulation of the pump G or 6a and by means of the safety alve 32 of Fig. l or the ,automatic pressurf regulator l1a of Fig.`2. The temperature c in be regulatedby the use of recording' gages or thermometers and by 95 control of thi: o il heater. It will be seen that the heated oil is circulated from the oil heater into he it inte'rchanging relation with `the liquid Within the precipitating. tanlqand r Vwith the entering liquid in thel inlet pipes T ioo and 7 In-1 i'actice, it is found that the temperaturen? the oil and liquid in the'precipitating tankr can be easily regulated and completeprecipitaton of the copper being.T a

obtained. y What I claii n. is: d.

1. An'appaiatus for precipitating copper from copper sulfate solutions `,by means of 12C sulfur. dioxid, comprisinga precipitating tank'provided with 'meansffor heating the .same to a suii able temperature, means for circulating" therethrough ,under a .suitable pressure the stint-ion to be preci itated, and

means for circilating the inilowing solution and the'hot oui flowing liquid Vintcrheat interchanging relat ,on `With each other; substantially'as described.

2. An apparatus for extracting Ycopper 130 from co per'bearing material with, sulfuric acid an for precipitatin the copper from the resulting copper sul ate solution, cor'nprising a leaching tank for leaching the fc'opp'er. bearing material with sulfuric acid,

a precipitating tank provided with means for heating the same to a suitable temperature, means for circulating through said precipitating tank in a continuous manner and under a suitable pressure the copper sulfate solution, together with sulfurdi'oxid, ,means for returning the outflowing liquid to the lcachingta'nk,l and means for circulatin the returning. hot liquid and the copper su fate solution flowing from the leaching tank to the precipitating' tankI .into heat interchanging relation lwith each other substantially as' described.

3. An apparatus for precipitating copper fronr copper sulfate solutions by means of sulfur dioxid, comprising a precipitating tank of considerable height provided withl an inlet near its bottom and an outlet near its top, means for heating said tank to a.

' suitable temperature,'means for circulating therethrough under a suitable pressure the solution 'to be precipitated, and means for 'drawing olf from the bottom of the tank the Vprecipitated copper without interfering with the continuous operation of the apparatus;

substantially as described.'

changing relation 'with said precipitating tank to heat the same b substantially as de- SGri ed. v

',Qopi-esof this patentmay be obtained for sulfur dioxid, comprisin 5. An apparatus for recipitating copper from copper sulfate so utions ',by means of tank having a double wa l for the circu1ation therethrough of heatin oil, means for4 circulating through said tan under a suitable pressure the solution to be precipitated,`

an oil heater, andmea'ns for circulatin the heatedoil through said double wall o the precipitating tank; substantially as .described.

6. An apparatus for precipitating copper from copper sulfate solutions by Ameans of sulfur dioxid, comprising a precipitating tank provided with means for heatin the same to a suitable temperature, a heat inter'- through said.

changer, means for circulatin heat interchanger and throug said precipitating tank in a continuous manner and under a suitable pressure the solution to be precipitated, and means for circula-ting the hot outowing liquid from said .precipitating tankthrough said heat interchanger; substantially as described.

7. An apparatus for precipitating copper from copper sulfate solutions by means of sulfur dioxid, comprising a precipitating tank, means for circulating therethrou h under al suitable pressure the solution t0 e precipitated, an'oil heater, means for circulating the heated oil into heat-interchanging relation with said precipitation tank to heat the same, and an expansion` tank arranged .above said precipitating tank and connected with the oil circulating system, whereby provsionis made for expansion of the oil without circulation of the heated oil through the expansion tank; substantially as described.

In testimony whereof I aflix my signature.

EDlVAR-D RAY WEIDLEIN.

ive cents. each, by, addressing the Commissioner of Patents, Washington, D. C.

a precipitating` 

